SCUDDER. NORTH AMERICAN CEUTHOPHILI. 21 



tional pair of spurs. Subgenital plate of male greatly produced 

 and apically deeply fissured. 



d 1 . Descending lobes of mesonotum slightly longer than 

 those of prouotum. Last tarsal joint very much shorter than 

 the remaining joints together, the third joint normal, though 

 but little shorter than the second. Subgenital plate of male 

 ample, rather deeply and broadly emarginate, the sides extend- 

 ing backwards as slender threads .... Phrixocnemis. 

 d 2 . Descending lobes of mesonotum no longer than those of 

 pronotum. Last tarsal joint about as long as the rest together ; 

 third tarsal joint wanting (as also on fore legs). Subgenital 

 plate of male immensely produced and so deeply fissured as to 



form two tapering ribbons Daihinia. 



c 2 . Third palpal joint shorter than the fifth, the inferior cleft of 

 the latter extending its whole length. Middle femora with a 

 genicular spine on posterior side. Hind tibia? slightly longer 

 than the hind femora, with numerous spines of the second grade 

 uniform in Ungth and pretty regularly separated; calcaria three 

 in number on each side, the middle one much longer than the 

 others. (First hind tarsal joint a third shorter than the rest 

 combined.) Subgenital plate of male ample, apically bitu- 



berculate Udeopsylla. 



a 2 . (Vertex bituberculate. Palpi short), the last joint apically with 

 no inferior cleft. Descending, lobes of mesonotum considerably longer 

 than those of pronotum ; sides of fore and middle coxae neither cari- 

 date nor spined. (Fore and middle femora unarmed.) Fore tibiae 

 sulcate above ; hind tibiae (of the same length as the hind femora) 

 with only one grade * of spines above on the lateral margins ; (calcaria 

 two in number on each side, subequal and not long. Third hind tar- 

 sal joint half as long as the second. Subgenital plate of male ample, 

 apically broadly and not deeply emarginate) ; outer valves of oviposi- 

 tor serrate above before the apex Gammarotettix. 



See introductory remarks. 



